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排序方式: 共有274条查询结果,搜索用时 15 毫秒
81.
D Lauque J Mazières P Rouzaud P Sié B Chamontin D Carrié C Hermant M Tubery P Carles 《Canadian Metallurgical Quarterly》1998,27(31):1566-1569
OBJECTIVES: The risk of thromboembolism in patients taking estrogen-progestagen oral contraceptive drugs has apparently increased since the introduction of third-generation progestagens (desogestrel, gestodene). We examined the clinical features, risk factors and outcome of pulmonary embolism in this context. PATIENTS AND METHODS: We reviewed 11 cases of thromboembolism in patients on oral contraception and hospitalized in emergency situations in 1995 and 1996 for pulmonary embolism in order to determine the gravity of the thromboembolic event, risk factors and type of drug used. RESULTS: Early clinical signs had preceded the onset of embolism by 2 to 164 days. PaO2 was below 70 mmHg in 4 patients. Diagnosis was achieved with pulmonary scintigraphy (11 cases), spiral CT (3 cases) and angiopneumography (2 cases). Duplex Doppler visualized the phlebitis in 7 patients. Given heparin (with fibrinolysis in 3 cases) then anti-vitamin K, and after withdrawal of the oral contraceptive, outcome was favorable in all cases. There were no recurrences. The nature of the oral contraceptive varied. Five patients were taking third-generation progestagens. In two cases, embolism had occurred following a change from a second-generation to a third-generation progestagen. Family history of phlebitis and/or abnormal laboratory findings were observed in 6 patients: resistance to activated protein C (2 patients), protein C deficiency (2 patients), anticardiolipin (2 patients) and low-titre antinuclear antibodies (2 patients). CONCLUSION: Pulmonary embolism in patients on oral contraceptives persists despite changes in the hormone content of the drugs. Diagnosis is often delayed. Family history of thrombosis or biological risk factors are often found. 相似文献
82.
When a reaction of the type A ? 2B (I) is accompanied by a parallel, autocatalytic reaction A + B ? 3B (II), the expression for the reciprocal relaxation time contains one concentration-independent term, derived from reaction (I) in the forward direction, and two terms linear in [B], one derived from reaction (I) in the reverse direction, and one derived from reaction (II) in the forward direction (in addition to a quadratic term). In such a case, the equilibrium constant for the reaction cannot be determined from relaxation experiments. It is suggested that the experimental results obtained in the acid hydrolysis of the dichromate ion can be explained on this basis. 相似文献
83.
Catherine J. Vladutiu Charles Poole Stephen W. Marshall Carri Casteel M. Kathryn Menard Harold B. Weiss 《Accident; analysis and prevention》2013
Background
Motor vehicle crashes are the leading cause of maternal injury-related mortality during pregnancy in the United States, yet pregnant women remain an understudied population in motor vehicle safety research.Methods
We estimated the risk of being a pregnant driver in a crash among 878,546 pregnant women, 16–46 years, who reached the 20th week of pregnancy in North Carolina (NC) from 2001 to 2008. We also examined the circumstances surrounding the crash events. Pregnant drivers in crashes were identified by probabilistic linkage of live birth and fetal death records and state motor vehicle crash reports.Results
During the 8-year study period, the estimated risk of being a driver in a crash was 12.6 per 1000 pregnant women. Pregnant women at highest risk of being drivers in serious crashes were 18–24 years old (4.5 per 1000; 95% confidence interval, CI,4.3, 4.7), non-Hispanic black (4.8 per 1000; 95% CI = 4.5, 5.1), had high school diplomas only (4.5 per 1000; 95% CI = 4.2, 4.7) or some college (4.1 per 1000; 95% CI = 3.9, 4.4), were unmarried (4.7 per 1000; 95% CI = 4.4, 4.9), or tobacco users (4.5 per 1000; 95% CI = 4.1, 5.0). A high proportion of crashes occurred between 20 and 27 weeks of pregnancy (45%) and a lower proportion of crashes involved unbelted pregnant drivers (1%) or airbag deployment (10%). Forty percent of crashes resulted in driver injuries.Conclusions
NC has a relatively high pregnant driver crash risk among the four U.S. states that have linked vital records and crash reports to examine pregnancy-associated crashes. Crash risks were especially elevated among pregnant women who were young, non-Hispanic black, unmarried, or used tobacco. Additional research is needed to quantify pregnant women's driving frequency and patterns. 相似文献84.
María Nela Pastuizaca Fernández Andrés Carrión García Omar Ruiz Barzola 《国际生产研究杂志》2013,51(7):2225-2238
Quality of a product is often measured through various quality characteristics generally correlated. Multivariate control charts are a response to the need for quality control in such situations. If quality characteristics are qualitative, it sometimes happens that the product quality is defined by linguistic variables – where quality levels are represented by some specific words – and product units are classified into several linguistic forms categories, depending on the degree of fulfilment of expectations, creating a situation of fuzzy classifications. This study first reviews the concepts found in the literature on the development of fuzzy multivariate control charts. We propose a method to control these fuzzy quality evaluations, with correlated multiple attributes quality characteristics, through the use of a Hotelling T2 control chart. 相似文献
85.
Tabares-da Rosa S Rossotti M Carleiza C Carrión F Pritsch O Ahn KC Last JA Hammock BD González-Sapienza G 《Analytical chemistry》2011,83(18):7213-7220
Single-domain antibodies (sdAbs) found in camelids lack a light chain, and their antigen-binding site sits completely in the heavy-chain variable domain (VHH). Their simplicity, thermostability, and ease in expression have made VHHs highly attractive. Although this has been successfully exploited for macromolecular antigens, their application to the detection of small molecules is still limited to a very few reports, mostly describing low-affinity VHHs. Using triclocarban (TCC) as a model hapten, we found that conventional antibodies, IgG1 fraction, reacted with free TCC with a higher relative affinity (IC(50) 51.0 ng/mL) than did the sdAbs (IgG2 and IgG3, 497 and 370 ng/mL, respectively). A VHH library was prepared, and by elution of phage with limiting concentrations of TCC and competitive selection of binders, we were able to isolate high-affinity clones, K(D) 0.98-1.37 nM (SPR), which allowed development of a competitive assay for TCC with an IC(50) = 3.5 ng/mL (11 nM). This represents a 100-fold improvement with regard to the performance of the sdAb serum fraction, and it is 100-fold better than the IC(50) attained with other antihapten VHHs reported thus far. Despite the modest overall antihapten sdAbs response in llamas, a small subpopulation of high-affinity VHHs is generated that can be isolated by careful design of the selection process. 相似文献
86.
Paula Marazuela Berta Paez-Montserrat Anna Bonaterra-Pastra Montse Sol Mar Hernndez-Guillamon 《International journal of molecular sciences》2022,23(9)
The pathological accumulation of parenchymal and vascular amyloid-beta (Aβ) are the main hallmarks of Alzheimer’s disease (AD) and Cerebral Amyloid Angiopathy (CAA), respectively. Emerging evidence raises an important contribution of vascular dysfunction in AD pathology that could partially explain the failure of anti-Aβ therapies in this field. Transgenic mice models of cerebral β-amyloidosis are essential to a better understanding of the mechanisms underlying amyloid accumulation in the cerebrovasculature and its interactions with neuritic plaque deposition. Here, our main objective was to evaluate the progression of both parenchymal and vascular deposition in APP23 and 5xFAD transgenic mice in relation to age and sex. We first showed a significant age-dependent accumulation of extracellular Aβ deposits in both transgenic models, with a greater increase in APP23 females. We confirmed that CAA pathology was more prominent in the APP23 mice, demonstrating a higher progression of Aβ-positive vessels with age, but not linked to sex, and detecting a pronounced burden of cerebral microbleeds (cMBs) by magnetic resonance imaging (MRI). In contrast, 5xFAD mice did not present CAA, as shown by the negligible Aβ presence in cerebral vessels and the occurrence of occasional cMBs comparable to WT mice. In conclusion, the APP23 mouse model is an interesting tool to study the overlap between vascular and parenchymal Aβ deposition and to evaluate future disease-modifying therapy before its translation to the clinic. 相似文献
87.
88.
Ana Paula L Veeck Bruna Klein Lauren F Ferreira Alexssandro G Becker Clarissa G Heldwein Berta M Heinzmann Bernardo Baldisserotto Tatiana Emanuelli 《Journal of the science of food and agriculture》2013,93(4):955-960
BACKGROUND: Lippia alba is effective in sedating and reducing stress to fish during transportation. Because some in vitro studies have demonstrated the antioxidant activity of L. alba, we hypothesized that its use in vivo could result in antioxidant effects post mortem. Therefore, in this study we evaluated whether the essential oil of L. alba (EO) used as sedative for fish transport would increase the lipid stability of fillets from silver catfish during frozen storage. RESULTS: The exposure to the EO in vivo did not affect conjugated diene values. However, EO (30 and 40 µL L?1) delayed the peak formation of peroxides (from the third to the sixth month of storage) and thiobarbituric reactive substances (from the ninth to the twelfth month of storage) when compared to control fillets. After exposure to 40 µL L?1 EO the free fatty acid content was higher than for control at the start of fillet storage, with no differences among groups thereafter. CONCLUSION: The essential oil of L. alba used as sedative in the water to transport silver catfish can delay lipid oxidation of fillets during frozen storage. Thus L. alba may be a promising source of natural active compounds for use in aquaculture and the food industry. © 2012 Society of Chemical Industry 相似文献
89.
Olga Borges Berta Gonçalves José L. Soeiro de Carvalho Paula Correia Ana Paula Silva 《Food chemistry》2008
Chemical composition of eight sweet chestnut cultivars from the three protected designation of origin (PDO) areas in the Trás-os-Montes region were studied: Aveleira, Rebordã, Trigueira and Zeive from PDO ‘Terra Fria’, Demanda, Longal and Martaínha from PDO ‘Soutos da Lapa’ and Judia from PDO ‘Padrela’. Chestnuts were characterised by high moisture content (∼50%), high levels of starch (43 g 100 g−1 dry matter – d.m.) and low fat content (3 g 100 g−1 d.m.). Nuts contained significant amounts of fibre (3% d.m.), were rich in K (∼750 mg 100 g−1 d.m.), P (∼120 mg 100 g−1 d.m.) and Mg (∼75 mg 100 g−1 d.m.). Moreover, chestnuts are a good source of total amino acids (6–9 g 100 g−1 d.m.). Amino acid profiles were dominated by l-aspartic acid, followed by l-glutamic acid, leucine, l-alanine and arginine. These results provide additional information about the nutritional value of each cultivar and confirm that chestnuts are an interesting healthy food. 相似文献
90.
New Trends in the Microencapsulation of Functional Fatty Acid‐Rich Oils Using Transglutaminase Catalyzed Crosslinking 下载免费PDF全文
Seyed Mohammad Taghi Gharibzahedi Saji George Ralf Greiner Berta N. Estevinho María José Frutos Fernández David Julian McClements Shahin Roohinejad 《Comprehensive Reviews in Food Science and Food Safety》2018,17(2):274-289
Preparing stable protein‐based microcapsules containing functional fatty acids and oils for food applications has been a big challenge. However, recent advances with transglutaminase (TGase) enzyme as an effective protein cross‐linker could provide workable solutions for the encapsulation of omega‐3 and omega‐6 fatty acids without compromising their targeted release and their biological and physicochemical characteristics. The recent and available literature related to the microencapsulation techniques, physical and oxidative properties, and core retention and release mechanisms of TGase‐crosslinked microcapsules entrapping edible oils were reviewed. The effects of factors involved in microencapsulation processes, on the efficiency and quality of the produced innovative microcapsules were also discussed and highlighted. A brief focus has been finally addressed to new insights and additional knowledge on micro‐ and nanoencapsulation of lipophilic food‐grade ingredients by TGase‐induced gelation. Two dominant microencapsulation methods for fish, vegetable, and essential oils by TGase‐crosslinking are complex coacervation and emulsion‐based spray drying. The developed spherical particles (<100 μm) with some wrinkles and smooth surfaces showed an excellent encapsulation efficiency and yield. A negligible release rate and a substantial retention level can result for different lipid‐based cores covered by TGase‐crosslinked proteins during the oral digestion and storage. A significant structural, thermal and oxidative stability for edible oils‐loaded microcapsules in the presence of TGase can be also obtained. 相似文献